Skip fire methodology involves selective cylinder deactivation to increase engine operating efficiency by disabling engine valves to reduce pumping losses when fewer cylinders are required for a particular operating point.
In similar methodology, a method of operating multi intake valve engines (multi-cylinder skip fire internal combustion engine systems), that is to say where each cylinder has more than one intake valve, involves deactivating only one intake valve for each multi intake valve cylinders in order to produce a swirl motion for the incoming charge air. This “swirl” mode of operation can replace “swirl valve” actuators used in some commercially available engines today, if the engines were to have valve deactivation hardware instead.
It is an object of the invention to provide a method of diagnosing such operation.
Prior art U.S. Pat. No. 9,562,470B2 patent by Tula Technology Inc. presents some methods for detecting valve actuation faults in a multi-cylinder skip fire internal combustion engine specifically to the end goal of detecting faults during skip fire operation.